Volume 18, No. 4, 2024
Received: 2024/05/04, Accepted: 2024/08/28
Authors:
Vishal Kushe; Sangita Mishra; Shrikant Charhate;
Abstract:
Due to a sharp increase in groundwater demands in coastal regions, groundwater levels are getting depleted day by day. The local groundwater table fluctuation eventually speeds up sea water intrusion. The present study investigates spatial and temporal groundwater level fluctuations to identify the area affected by sea water intrusion & also for sustainable water resources management in coastal stretch of Sindhudurg district, Maharashtra which is about 121 km. Using groundwater level data collected from Central Ground Water Board (CGWB), Sindhudurg for a period from 1991 to 2022, fluctuations of groundwater levels were examined. The collected levels were evaluated for monsoon, pre-monsoon & post-monsoon seasons and every level were interpolated over study area using Inverse Distance Weighted Method as spatial interpolation technique in QGIS 3.22.1, in order to obtain actual difference in groundwater levels. According to results, groundwater level varies from 1.88 to 13.45 m below ground level (bgl) in pre-monsoon season, from 0.1 to 7.05 m bgl in post-monsoon season & from 1 to 10.6 m bgl in monsoon season. Using statistical tests like Mann-Kendall test & Sen's slope estimator, the pattern of variation of groundwater levels was anticipated. According to findings, over 80% of the basin has a falling water table during monsoon season. It was observed that groundwater level in pre-monsoon was more as compared to monsoon and post-monsoon season in entire study area. The overall outcome of the study demonstrates that groundwater level fluctuations were non uniform in study area which may cause increase in sea water intrusion leading to decrease in crop production.
Keywords:
GIS, Ground water level, Sea water intrusion, Mann Kendall test, Spatial interpolation, Sen’s slope estimator.